The Local Inflammatory Responses to Infection of the Peritoneal Cavity in Humans: Their Regulation by Cytokines, Macrophages, and Other Leukocytes

摘要

Studies on infection-induced inflammatory reactions in humans rely largely on findings in the blood compartment. Peritoneal leukocytes from patients treated with peritoneal dialysis offer a unique opportunity to study in humans the inflammatory responses taking place at the site of infection. Compared with peritoneal macrophages (pMϕ) from uninfected patients, pMϕfrom infected patients displayex vivoan upregulation and downregulation of proinflammatory and anti-inflammatory mediators, respectively. Pro-IL-1βprocessing and secretion rather than synthesis proves to be increased in pMϕfrom infectious peritonitis suggesting up-regulation of caspase-1in vivo. A crosstalk between pMϕ,γδT cells, and neutrophils has been found to be involved in augmented TNFαexpression and production during infection. The recent finding in experimental studies that alternatively activated macrophages (Mϕ2) increase by proliferation rather than recruitment may have significant implications for the understanding and treatment of chronic inflammatory conditions such as encapsulating peritoneal sclerosis (EPS).